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|
Attributes | |
ACN | 1137448 |
Time | |
Date | 201312 |
Local Time Of Day | 0001-0600 |
Place | |
Locale Reference | ZZZ.Airport |
State Reference | US |
Environment | |
Flight Conditions | VMC |
Light | Night |
Aircraft 1 | |
Make Model Name | B737-700 |
Operating Under FAR Part | Part 121 |
Flight Phase | Climb |
Flight Plan | IFR |
Component | |
Aircraft Component | Horizontal Stabilizer Trim |
Person 1 | |
Function | First Officer Pilot Not Flying |
Experience | Flight Crew Last 90 Days 195 Flight Crew Type 7932 |
Person 2 | |
Function | Captain Pilot Flying |
Experience | Flight Crew Last 90 Days 245 Flight Crew Type 16000 |
Events | |
Anomaly | Aircraft Equipment Problem Critical Deviation - Procedural Published Material / Policy |
Narrative:
The first indication of the problem occurred during climb out. The captain was the pilot flying and noted that his elevator trim switch was intermittent. After our initial level off; the captain engaged autopilot a. Within a few minutes we noted the stab out of trim light had illuminated; but extinguished within approximately 10 seconds as the autopilot began to trim the aircraft once again. A few minutes later the light illuminated again. We also noted a momentary speed trim fail light. The stab out of trim light illuminated and extinguished again several times.the captain asked me to run the stabilizer out of trim checklist from the QRH. As I was running the checklist; the autopilot kicked off and the trim wheel had stopped moving. The captain noted heavy down force pressure on the control column as he flew the aircraft by hand. He slowed the aircraft to around 270-280 KTS to lighten the control column pressure. I completed the stabilizer out of trim checklist and began the stabilizer trim inoperative checklist. ATC was step-climbing us behind another aircraft and the constant radio calls; climbs and level offs were very distracting. By the time we realized the extent of our malfunction; we were half way to our destination. We were only able to trim nose down; either manually with the trim wheel or with the electric trim switches. I discovered that I was able to move the trim wheel nose up; a little at a time; if I moved the trim wheel very slightly nose down first. But we moved it only enough to keep the aircraft controllable because it was binding. After completing the first portion of the stabilizer trim inoperative checklist; we traded off hand-flying the aircraft. We contacted dispatch and determined it would be best to continue to our filed destination. We declared an emergency with center; and once with approach control; requested vectors for a 10-mile straight-in to runway xxl. The airport was landing another runway; but runway xx gave us an additional 3;083 ft and worked with the winds. The captain discussed the situation with the flight attendants after we had determined our course of action and had me convey to them that we anticipated a normal landing after we were fully configured and the aircraft was controllable. We determined to not notify the passengers. We completed all required items on the stabilizer trim inoperative checklist and landed without incident. Once cleared by the responding emergency vehicles; the captain taxied the aircraft to the gate.
Original NASA ASRS Text
Title: A B737-700 stabilizer trim siezed during climb with Stab Out of Trim light and Speed Trim Fail lights illuminated but the crew could manually trim nose up after a slight nose down input. The QRH was completed and an emergency was declared for the landing.
Narrative: The first indication of the problem occurred during climb out. The Captain was the pilot flying and noted that his elevator trim switch was intermittent. After our initial level off; the Captain engaged Autopilot A. Within a few minutes we noted the Stab Out of Trim light had illuminated; but extinguished within approximately 10 seconds as the autopilot began to trim the aircraft once again. A few minutes later the light illuminated again. We also noted a momentary Speed Trim Fail light. The Stab Out of Trim light illuminated and extinguished again several times.The Captain asked me to run the Stabilizer Out of Trim Checklist from the QRH. As I was running the checklist; the autopilot kicked off and the trim wheel had stopped moving. The Captain noted heavy down force pressure on the control column as he flew the aircraft by hand. He slowed the aircraft to around 270-280 KTS to lighten the control column pressure. I completed the Stabilizer Out of Trim Checklist and began the Stabilizer Trim Inoperative Checklist. ATC was step-climbing us behind another aircraft and the constant radio calls; climbs and level offs were very distracting. By the time we realized the extent of our malfunction; we were half way to our destination. We were only able to trim nose down; either manually with the trim wheel or with the electric trim switches. I discovered that I was able to move the trim wheel nose up; a little at a time; if I moved the trim wheel very slightly nose down first. But we moved it only enough to keep the aircraft controllable because it was binding. After completing the first portion of the Stabilizer Trim Inoperative Checklist; we traded off hand-flying the aircraft. We contacted Dispatch and determined it would be best to continue to our filed destination. We declared an emergency with Center; and once with Approach Control; requested vectors for a 10-mile straight-in to Runway XXL. The airport was landing another runway; but Runway XX gave us an additional 3;083 FT and worked with the winds. The Captain discussed the situation with the flight attendants after we had determined our course of action and had me convey to them that we anticipated a normal landing after we were fully configured and the aircraft was controllable. We determined to not notify the passengers. We completed all required items on the Stabilizer Trim Inoperative Checklist and landed without incident. Once cleared by the responding emergency vehicles; the Captain taxied the aircraft to the gate.
Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.